Development Of A New,Simple Cough Assessment Test And Evaluation Of Chronic Cough Assessment Tools

Part Ⅰ A New Score of Cough: Development and Validation of the Cough Evaluation Test BackgroundChronic cough causes a significant impact on quality of life,including physical,psychological and social aspects.Nevertheless,there is no simple method which could evaluate cough severity and its impact on quality of life.Developing a new simple score of cough is practical and meaningful for the evaluation and management of the patients with cough.ObjectiveTo develop and validate a new simple score of cough which can evaluate cough severity and its impact on quality of life.Methods1.Item generation: A list of items were generated based on literature review and clinical practice.2.Item screening: Screening the items was conducted by the Delphi method,and the Cough Evaluation Test(CET)was generated.3.Validation: The patients with chronic cough and subacute cough from respiratory clinics in seven general hospitals in Guangdong province were recruited to validate the CET.The CET,Cough Visual Analog Scales(VAS)and Mandarin Chinese version of the Leicester Cough Questionnaire(LCQ-MC)were completed by the patients before the treatment to evaluate internal consistency reliability and concurrent validation.Reassessments of the CET were performed at 1 week apart before treatment and after more than 1 week to evaluate repeatability and responsiveness,respectively.4.Cronbach’s alpha coefficient was used to evaluate internal consistency.Spearman rank correlation coefficients were used to determine relationships within different outcome measures.The repeatability was assessed using intraclass correlation coefficient and Bland-Altman plot.The responsiveness was evaluated by paired t test and effect size.Effect size for CET was determined by the difference in mean CET score before and after the intervention/SD of CET score before the intervention Results1.There were 13 items in the preliminary CET which consisted of cough severity and its impact on physical,social and psychological aspects.2.The CET consisted of 5 items at last,including “Cough during the day”,“Cough disturbed sleep ”,“Intense cough ”,“Cough interfered with daily life ” and “Feeling anxious”.A 5 point Likert scale was used,the score of each item ranged from 1to 5 and the total score ranged from 5 to 25 for CET,the higher score means more severe cough symptom or worse quality of life.3.A total of 293 patients with cough were enrolled,including 247 patients with chronic cough and 46 patients with subacute cough.Patients had a mean(standard deviation)age of 40.0(12.7)years,cough duration of 8.0(0.8-600)months,and 56.3%were women.Cronbach’s alpha coefficient of CET was 0.803.CET showed moderate correlations with VAS(r =0.692,P<0.001)and LCQ-MC(r=-0.743,P<0.001).VAS showed moderate correlation with LCQ-MC(r=-0.585,P<0.001).The correlations between CET and VAS\LCQ-MC were stronger than that between VAS and LCQ-MC.Repeatability was tested in 55 patients and the intraclass correlation coefficient of CET was 0.922.Responsiveness was tested in 127 patients who had therapeutic intervention,whose mean(standard deviation)score of CET was 14.3(4.0)before treatment and decreased to 9.4(3.8)after treatment.The change in CET score after treatment was significant(P<0.001).ConclusionsCough Evaluation Test shows good internal consistency reliability,concurrent validation,repeatability and responds well to the change of cough severity after the treatment,suggesting CET is a simple,valid and reliable tool to evaluate severity of cough and its impact of quality of life in the patients with chronic cough and subacute cough.Part Ⅱ Evaluation of the Reliability,Validity and Responsiveness of Chronic Cough Assessment ToolsBackground There was still a lack of sufficient data to prove the validity of the common chronic cough assessment tools,including Cough Visual Analog Scales(VAS),Mandarin Chinese version of Cough Symptom Score(CSS)and Mandarin Chinese version of the Leicester Cough Questionnaire(LCQ-MC).And the minimal clinically important difference(MICD)of VAS and LCQ-MC had not been reported.Objective We aim to evaluate the reliability,validity and responsiveness of VAS,CSS and LCQ-MC and to detect the minimal clinically important difference(MICD)of VAS and LCQ-MC in chronic cough patients.Methods1.The patients with chronic cough from Cough Clinic in the First Affiliated Hospital of Guangzhou Medical University from July 2017 to January 2020 were admitted.The patients completed VAS,CSS and LCQ-MC before the treatment to evaluate the tools of internal consistency reliability and concurrent validation.Reassessments were performed in patients whose cough did not change at 1 week apart before treatment to evaluate the repeatability of the tools.In addition to the above tools,the patients needed to complete the Global Rating of Change Questionnaire(GRCQ)after more than 1 week to evaluate the responsiveness of the tools and to detect their minimal clinically important difference,respectively.2.Cronbach’s alpha coefficient was used to evaluate internal consistency.Spearman rank correlation coefficients were used to determine relationships between different outcome measures.The repeatability testing was assessed using intraclass correlation coefficient and Bland-Altman plot.The responsiveness was evaluated by paired t test and effect size.Effect size was determined by the difference in mean score before and after the intervention/SD of score before the intervention.Calculating the absolute value of the mean difference between the questionnaire scores before and after treatment and standard error of measurement(SEM)value to detect the minimal clinically important difference.Results1.193 patients were recruited to complete VAS,CSS and LCQ-MC.Patients had amean(standard deviation)age of 40.3(12.4)years,cough duration of 18.0(2-600)months,and 52.3% were females.It showed the Cronbach’s alpha coefficients of LCQ-MC was0.793.2.There were moderate correlations between CSS and VAS and that between CSS and LCQ-MC(r=0.648,P<0.001;r=-0.472,P<0.001,respectively).VAS also showed moderate correlation with LCQ-MC(r=-0.534,P<0.001).3.Reassessments were performed in 58 patients and the ICC of VAS,CSS and LCQ-MC were 0.862,0.822 and 0.830,respectively.4.Responsiveness was tested in 68 patients who had therapeutic intervention,their mean(standard deviation)scores of VAS,CSS and LCQ-MC before treatment were 57.7(20.2),4.2(1.4),12.2(3.1),respectively.After treatment,their scores decreased to30.8(20.7),2.8(1.5),15.3(3.3),respectively.The scores of VAS,CSS and LCQ-MC changed significantly after treatment(P<0.001).5.The minimal clinically important difference of VAS and LCQ-MC were 15 mm and2.0,respectively.Conclusions LCQ-MC shows good internal consistency reliability.VAS,CSS and LCQ-MC all show good concurrent validation,repeatability and are responsive well to the change of cough severity after the treatment.The minimal clinically important difference of VAS and LCQ-MC in chronic cough were 15 mm and 2.0,respectively.